1. Technical Field
The present invention relates to a solid-state image capturing device and a manufacturing method thereof.
2. Related Art
In a conventional solid-state image capturing device, carriers generated in a photodiode due to photoelectric conversion are transferred via a transfer path to a floating diffusion layer in which the carriers are temporarily accumulated (refer to JP-A-6-338524, for example).
In the above solid-state image capturing device, a larger transfer path width is desirable in order to efficiently transfer the carriers generated in the photodiode due to photoelectric conversion to the floating diffusion layer. On the other hand, in order to increase a conversion gain with which the electric charge of the carriers generated due to photoelectric conversion is converted to a voltage in the floating diffusion layer, a smaller capacitance (cross-sectional area) of the floating diffusion layer is desirable, and thus, the transfer path width needs to be small. Therefore, it has been difficult to reduce the capacitance of the floating diffusion layer while increasing the transfer path width.